Generally, a cowl panel is required to have a high degree of freedom of interior design, a glass-supporting stiffness capable of supporting a front window member, and pedestrian protection performance. Based on this, the present inventors are considering adopting in a front body structure of a vehicle, a cowl panel whose cross section perpendicular to a vehicle width direction has a substantially S shape as shown in FIG. 14.
This cowl panel 84 includes a protruding portion 82 and a vertical wall portion 83. The protruding portion 82 protrudes in a forward direction and is located under a portion of the cowl panel 84 which supports a front window member 81. The vertical wall portion 83 extends in a downward direction from a lower end of the protruding portion 82.
Since the cowl panel 84 is configured as above, a large space can be secured behind the protruding portion 82, so that the degree of freedom of the interior design can be improved. In addition, since the protruding portion 82 expands in the forward direction, the glass supporting stiffness can be secured. Further, when a collision load shown by an arrow in FIG. 14 is applied to the cowl panel 84, the protruding portion 82 deforms to absorb collision energy, and then, the vertical wall portion 83 falls in a rearward direction and the downward direction to further absorb the collision energy. Since the cowl panel 84 absorbs the collision energy in two steps, the pedestrian protection performance can be secured.
However, as shown in FIG. 14, in a case where a front end opening portion (so-called duct opening) of an outside air introducing duct 86 of an air conditioner 85 is connected to a passenger seat-side rear surface of the cowl panel 84 via a urethane member 87 and/or the like, the following problems occur. To be specific, when the collision load is applied to the cowl panel 84, the cowl panel 84 deforms as shown by a chain double-dashed line α in FIG. 14. At this time, the outside air introducing duct 86 is sandwiched by the protruding portion 82 of the deformed cowl panel 84 having the substantially S-shaped cross section. Thus, the outside air introducing duct 86 deforms so as to be bent as shown by a dotted line β in FIG. 14 about a bent point β1 in FIG. 14 (this deformation is hereinafter referred to as “bending deformation”).
More specifically, because of the bending deformation of the outside air introducing duct 86, a load in a direction perpendicular to an axis extending through a center of a closed cross section of the outside air introducing duct 86, that is, a load in such a direction that the duct 86 is easily crushed, is hardly transferred to portions β2 and β3 located at the air conditioner side of the bent point β1. These portions β2 and β3 receive the collision load mainly in a direction along a central axis of the closed cross section of the duct, the direction being such a direction that that the duct 86 is hardly crushed. Therefore, the outside air introducing duct 86 becomes stiff between the cowl panel 84 and a vehicle body. Thus, the front end opening portion of the outside air introducing duct 86 is sandwiched by and stuck in the protruding portion 82 of the cowl panel 84, and this inhibits the deformation of the protruding portion 82 of the cowl panel 84 and the rearward and downward falling of the vertical wall portion 83. As a result, it is presumed that the absorption of the collision energy by the deformation of the cowl panel 84 is inhibited. As above, it was found that a problem occurs, in which in a case where the outside air introducing duct 86 is connected to the cowl panel 84, and even if the front end opening portion and bent point 131 of the outside air introducing duct 86 have deformed, the outside air introducing duct 86 inhibits the absorption of the collision energy by the cowl panel 84.
PTL 1 discloses a front body structure of a vehicle, the front body structure including a front cowl and an air conditioning unit. The front cowl has a U shape in a side view of the vehicle body. The air conditioning unit is configured such that an opening edge portion of an outside air introducing port through which outside air is introduced through an internal space of the front cowl is coupled to a rear vertical wall of the front cowl by bolts. To promote plastic deformation of the front cowl when the front cowl receives an impact, a weak portion having a “dogleg shape” in a side view is formed at each of a vertical-direction intermediate portion of the opening edge portion of the outside air introducing port of a duct of the air conditioning unit and a vertical-direction intermediate portion of a portion of the rear vertical wall to which the opening edge portion is coupled by the bolts. To be specific, according to this conventional structure disclosed in PTL 1, the weak portions prevent the rear vertical wall of the front cowl from becoming too strong since the opening edge portion (corresponding to a front end opening portion of the present invention) of the duct that is high in stiffness is fastened by the bolts. However, PTL 1 does not disclose either of the technical problem and configuration of the present invention.